Plug fuse with a replaceable fuse link



June 4, 1935'.

J. ROSENBAUM 2,003,792

PLUG FUSE WITH A REPLACEABLE FUSE LINK Filed March 13, 1954 FIG 1 FIG 11 IN V EN TOR.

Patented June 4, 1935 PATENT OFFICE PLUG FUSE WITH A REPLACEABLE FUSE LINK Joel Rosenbaum, West Orange, N. J.

Application March 13, 1934, Serial No. 715,261

3 Claims.

The invention relates to improvements in plug fuses in which the fuse link is replaceable; and the objects of the improvements are, first, to afford a simple and inexpensive means of replacement of the fuse link; second, to afford facilities for proper contact between fuse link and fuse; and third, to provide sufficient room for proper fusing of the link. The nature of the invention is such that it does away with certain fundamental objections encountered in usual plug fuses with non-replaceable link heretofore introduced on the market, such as; the necessity of replacing the entire fuse notwithstanding the fact that only the fuse element or link is destroyed, and the possibility of shock transmitted to the person changing fuses by means of the metallic band necessary to hold the top on such fuses.

One form of the invention is illustrated in the accompanying drawing, in which Figure l is a side view of the entire fuse; Figure 2, an enlarged vertical section of the entire fuse on the line 2-2, Figure 4; Figure 3, a plan view of bottom washer 4; Figure 4, a bottom view of top, I; Figure 5, a bottom view of shell contact, 3; Figure 6, a plan view of body and shell contact; Figure 7, a plan view of bottom contact stay washer, 5; Figure 8, a bottom view of body, 2; Figure 9, a side view of contact spring, 9; Figure 10, a side view of contact spring, 6; and

Figure 11, a plan view of fuse link, I I.

By referring to the drawing, and more particularly to Figure 2, it will be seen that the device of my invention comprises, in combination, a shell of insulating material and a fuse link of conducting material. The insulating material of the shell and the conducting materials of shell contact II, springs 6 and 9, prongs 8-8, stays on prongs 8-8, bottom contact stay washer 5, 40 pin I0, and fuse link II are to be of materials used in standard practice as recommended by the Underwriters laboratories. The shell consists of top I, body 2, and a bottom plate or washer 5. The parallel spaced prongs 8-8 may be attached to or cast in top I, and corresponding parallel spaced wells are provided in the body 2. The wells extend the entire depth of the body 2. Contained in the wells are springs 6 and 9. The springs 6 and 9 both hold the top 5 spaced wells of the body 2, and is held against the contact seats provided by the springs 6 and 9 by suitably placed stays on the prongs 8-8. The stays on the prongs 8-8 serve two purposes, namely; to hold the fuse link II, firmly on the contact seats provided by the springs 6 and 9, 5 and to provide better contact between the fuse link, prongs, and springs. The stays on the prongs may be made an integral part thereof or they may be threaded thereon in accordance with the expediency of manufacture thereof. 10 Adequate space for the fusion of the fuse link I I is provided by a well or depression immediately under the fuse link II. Pin III is cast in body 2.

The installation of the fuse link II and operation of the device of my invention is of the 15 most extreme simplicity. The fuse link II, may be inserted in the following manner: first the top I, is removed by a pull which releases prongs 8-8 from springs 9 and 6 and allows springs to fall into position indicated by 9' and 6; second, the link II is placed over prongs 8-8; and finally the top I and the body 2, are fastened together by a push and are held together by springs 9 and B. The bottom contact stay washer 5 together with pin I0 constitutes the center contact of the fuse. The path of the current is from the center contact, to spring 6, to prong 8, to fuse link II, to prong 8 on opposite side, to spring 9, to shell contact 3.

Obviously by removing the top I from the body 2, the condition of the link II may readily be ascertained without the necessity of removing the body 2 from the fuse box. The fuse link may then be inserted as described above.

I am aware that prior to my invention, plug fuses with replaceable links, have been made. I therefore do not claim such a combination broadly; but

I claim:

1. A plug fuse with a replaceable fuse link, comprising, in combination, a. shell of insulating material and a fuse link, the body of said shell having parallel spaced wells, of a depth equal to that of said body, springs in said wells, said springs extending the full length of said wells, and bent over top of said body to provide a contact seat for said fuse link, a fusing depression in said body, said fusing depression allowing sufiicient space for the link to fuse readily and completely, a top for said shell, said 50 top fitted snugly over said body, parallel spaced prongs attached to said top, adapted to be inserted in said wells in said body, stays placed on said prongs so as to press said fuse link against the said contact seats provided by said r springs, said fuse link having a pair of spaced slots therein, adapted to .allow said prongs to slip thru said slots and hold said link against said spring contact seat.

2. A plug fuse with a replaceable link, comprising, in combination, a fuse link and a casing of insulating material consisting of a body, top, and a bottom plate or washer, said body having parallel spaced apertures extending substantially the depth thereof, said apertures ,containing springs running the full length of said apertures and being bent at the top of said body to provide a contact seat for said fuse link, said top fitting snugly over said body, par

allel spaced prongs attached to said top, adapt-" ed to slide thru spaced slots in said fuse link and into the said parallel spaced apertures of the said body, said prongs being 1constructed with stays so placed as to press thesaid fuse link against the said spring contact Seats.

315 plug fuse with a replaceable fuse link,

comprising, in combination, a shell of insulating material and a fuse link, said shell to consist of a top, body, and a bottom plate or washer, said top held to said body by the insertion of parallel spaced prongs attached to said top, into corresponding parallel spaced wells of the said body, said wells extending the entire depth of said body and containing springs which both hold said top to said body and also provide contact seats for the said fuse link, inasmuch as said springs run the full length of said wells and are bent over on the top of the said body,

said fuse link to have spaced slots conforming to said parallel spaced wells of said body ,and to be held in place against the said spring contact seats by inserting the said parallel spaced prongs thru said slots and also by suitably placed stays on said prongs, said body having a well or depression beneath said link to provide adequate room JOEL ROSENBAUM.

for fusing of said link. 20 

